Various devices have been devised for preventing theft or operation of cycles or motor cycles, by disabling operation of a handlebar control lever. For example U.S. Pat. No. 4,426,861 to Chillis, U.S. Pat. No. 5,347,835 to Dewey, U.S. Design Pat. No. 351,983 to Young et. al., U.S. Pat. No. 5,511,399 to Lynn, and U.S. Design Pat. No. 402,180 to Chappell (the present applicant).
All of these devices are addressed to immobilizing the hand brake lever or a similar lever of a motor cycle of the like, by attempting to secure this in relation to the handlebar grip region. However, all of these devices except those of Chappell and Young et. al. comprise two or more components which must be fitted together in use, making handling difficult. The devices of Chappell and Young et. al. comprise two members hinged together, thus simplifying handling. However, neither of these devices have means for fine adjustment of a handlebar control lever such as a brake lever or clutch, in relation to the handlebar. Such fine adjustment can be an advantage in ensuring the brake is locked on in all cases, irrespective of the condition of the brake lever adjustment, and irrespective of different dimensions for different makes of bicycles. Moreover, when used with a clutch lever, this fine adjustment enables the clutch to be locked in a desired position.
Another desirable feature of an anti-theft device is one which can securely lock rotation of the handlebar grip region, which in the case of a twist grip throttle, would provide further security in preventing the engine from being operated. Again neither of the designs of Chappell or Young et. al. have adjustment means to achieve this.